Endocrine Abstracts

Swyer syndrome (pure gonadal dysgenesis) is characterised by female phenotype with a 46 XY genotype due to a mutation of the sex determining region (SRY) gene on the y chromosome. A 28 year old presented with back pain after an accident and had a 2nd lumbar vertebral fracture and severe osteoporosis. The DEXA scan T score was −4.2. Procollagen Type 1 pro peptide and Osteocalcin levels were high. She had been in good health and denied any family illness. She was 180 cm tall and weighted 63 kg. Breasts were present though not fully developed. She had sparse pubic and axilliary hair. The external genitalia were normal. She had high gonadotropins and low oestrogen and testosterone levels. She had normal serum calcium, phosphate, parathyroid hormone, and vitamin D levels. coeliac and immunoglobulin screen was negative. She had no liver or renal disease. The patient reported menstruating from age 14. Genotype was 46XY -normal male. PCR analysis confirmed the SRY locus on the Y chromosome. MRI and ultrasound of pelvis showed a uterus, fallopian tubes, vagina and one streak gonad. Anti Mullerian factor was low. There is the first reported case of severe osteoporosis as the presentation of Swyer syndrome. It improved with a 29% increase in T score over 2 years with recombinant parathyroid hormone. She menstruated for the first time on cyclical oestrogen. She underwent gonadectomy for the risk of malignancy. Osteoporosis and tall stature were due to life long oestrogen deficiency.The patient later admitted she had concealed primary amenorrhoea for cultural reasons delaying early diagnosis and treatment.